How To Convert An Elixir Binary To A String?

There's a couple of things here:

1.) You have a list with a tuple containing one element, a binary. You can probably just extract the binary and have your string. Passing the current data structure to to_string is not going to work.

2.) The binary you used in your example contains 0, an unprintable character. In the shell, this will not be printed properly as a string, due to the fact that Elixir can't tell the difference between just a binary, and a binary representing a string, when the binary representing a string contains unprintable characters.

3.) You can use pattern matching to convert a binary to a particular type. For instance:

iex> raw = <<71,32,69,32,84,32>>
...> Enum.join(for <<c::utf8 <- raw>>, do: <<c::utf8>>)
"G E T "
...> <<c::utf8, _::binary>> = raw
"G"

Also, if you are getting binary data from a network connection, you probably want to use :erlang.iolist_to_binary, since the data will be an iolist, not a charlist. The difference is that iolists can contain binaries, nested lists, as well as just be a list of integers. Charlists are always just a flat list of integers. If you call to_string, on an iolist, it will fail.

I made a function to convert binary to string

def raw_binary_to_string(raw) do
   codepoints = String.codepoints(raw)  
      val = Enum.reduce(codepoints, 
                        fn(w, result) ->  
                            cond do 
                                String.valid?(w) -> 
                                    result <> w 
                                true ->
                                    << parsed :: 8>> = w 
                                    result <>   << parsed :: utf8 >>
                            end
                        end)

  end

Executed on iex console

iex(6)>raw=<<65, 241, 111, 32, 100, 101, 32, 70, 97, 99, 116, 117, 114, 97, 99, 105, 111, 110, 32, 65, 99, 116, 117, 97, 108>>
iex(6)>raw_binary_to_string(raw)
iex(6)>"Año de Facturacion Actual"